I just installed Ubuntu 12.10 (32bit) and everything seems to be working fine with the exception that the only resolutions that the Display Settings dialog allow me to set are 800x600 and 1024x768.

I'm using a computer with Intel Integrated Graphics Chipset 945G, and Benq T71W monitor which is capable of running 1440x900 (which is the resolution I want). Other system information that may be relevant: the processor is Intel Core2 Duo CPU E4500 @ 2.20GHz × 2 and the system has 994.9MB of memory.

In case more information is needed, this is some of the output of "lspci -v | less":

I've found that I can use xrandr to set the resolution to 1440x900, the problem is that the change is not permanent and causes an error message at the next startup. I've read that I can use xorg.conf to make it permanent but not only I couldn't find the file, but I've also read comments saying that the file is not used anymore and using it was not advisable or something like that.

Even if the system can't seem to identify my monitor, it recognizes it can handle resolutions higher than the ones it allows to use through the display dialog. This is the output of "xrandr -q":

So, the question is, how can I solve the issue? I'd like to avoid using a script on startup as I've read that it causes a slowdown. Is there a way to make the desired resolution appear in the display dialog and make it stay as a valid option even after reboot?